The present invention relates to an automatic focusing camera, and more particularly, is directed to an automatic focusing camera in which the shutter speed corresponding to the opening and closing of the shutter aperture is determined from the speeds of a plurality of moving objects.
Conventionally, as disclosed in Japanese Patent Application No. SHO61-309531, entitled "Automatic Focusing Unit for Still Camera", the distance to a moving object is observed at a plurality of predetermined times and the position of the object at the time of opening and closing the shutter aperture is determined from the observed range data.
Also, a method in which ranges to the center, as well as to left and right, objects are observed and the focal point is determined based on these ranges to the center, left and right objects, has been disclosed in Japanese Patent Application No. SHO63-199368 entitled "Automatic Focusing Camera".
Furthermore, in Japanese Patent Publication No. 57-153610, incident light from an object is received at two light-receiving points and the light path of the object is determined by solid state elements disposed in parallel, thus forming a range-finding circuit having no mechanical driving system for focusing a lens.
In Japanese Patent Application No. SHO63-199368 and the Japanese Patent Publication, a plurality of light-receiving elements or luminous elements which are disposed in parallel are used as one side of a range finder and the active state on a light path of light-receiving elements or luminous elements which are disposed in parallel for the light is used as another side of the range finder, and a measured value is determined by the active states of elements provided on one side and the other side which are in accord with each other.
In the abovementioned three patent applications, the desired automatic focusing operation is performed from obtained range data or range data of a plurality of objects.
The arrangement of Japanese Patent Application No. SHO63-199368 has been provided for the purpose of preventing so-called center missing when the release button is pushed down to a first stroke to obtain a focused state for both left and right objects so as to perform a focusing operation, even in the case where an object does not exist at the center, and when the pertinent shutter opration cannot be performed when the object is moving.
Also, in Japanese Patent Application No. SHO63-309531 the distance to a moving object at the time of opening and closing the shutter aperture may be determined from the previously-determined distance to the moving object, and in the Japanese Patent Publication, the distance to an object may be obtained but the speed of the object cannot be obtained. Accordingly, a still picture of an object cannot be taken at an appropriate shutter speed.